Mesa (main): nir: Lower all bit sizes of usub_borrow

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Module: Mesa
Branch: main
Commit: 17557303625d95fc30b24d15b45e41d9b747aee6
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=17557303625d95fc30b24d15b45e41d9b747aee6

Author: Jason Ekstrand <jason.ekstrand at collabora.com>
Date:   Mon Apr 25 12:12:10 2022 -0500

nir: Lower all bit sizes of usub_borrow

It's not clear why this is restricted to 32-bit besides that being the
only bit size where GLSL has an intrinsic for this.  All drivers that
set this probably want it lowered for all bit sizes as far as I can
tell.

Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/6353
Fixes: 8a3e3441802c ("nir/opt_algebraic: Fix some expressions with ambiguous bit sizes")
Reviewed-by: Emma Anholt <emma at anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16146>

---

 src/compiler/nir/nir_opt_algebraic.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py
index 830a5377199..3eba54f675f 100644
--- a/src/compiler/nir/nir_opt_algebraic.py
+++ b/src/compiler/nir/nir_opt_algebraic.py
@@ -1655,7 +1655,7 @@ optimizations.extend([
    (('fmod', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
    (('frem', a, b), ('fsub', a, ('fmul', b, ('ftrunc', ('fdiv', a, b)))), 'options->lower_fmod'),
    (('uadd_carry', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
-   (('usub_borrow at 32', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
+   (('usub_borrow', a, b), ('b2i', ('ult', a, b)), 'options->lower_usub_borrow'),
 
    (('bitfield_insert', 'base', 'insert', 'offset', 'bits'),
     ('bcsel', ('ult', 31, 'bits'), 'insert',